Apparatus for making plates for artificial teeth.



L. H. SPRINKLE.

APPARATUS FOR MAKING PLATES FOR ARTIFICIAL TEETH. APPLICATIQN FILED JAN. 6. 1916.

1 96,478. Patented Nov. 28, 1916.

WITNESS Ill/MENTOR LAKE H. J'PRi/V/(LE.

A TTORNEV t dinel section of a potion.

Evaluato /n e't may concem Beit lmown that I, LAKE H. SPRINKLE,- eoitiz en of the United States, resicling at -liirooizlyn, in the ounty of Kings and State wQili'litllVi York, have invented certuin new anti useful improvements in Apparatus for linking Plates for Artificial Teeth, of which I ,the i'ollowing is specification.

have invented certain improvements in connection with the making of plates c'oinmonly used for supportingnartificial teeth in'the human mouth; and particularly'an sppere-ins for casting se-hlmouth plates in .a manner that hath evoidswaste and loss end at the same time results in a very superior proriuct.

- ,;A.- 110St important object ofrhy invention;-

) is to provide a construction whereby the mold in which such mouthplates are formed can be conveniently and quickly inspect cu and cleaned as soon assitgis in ;condition to he used; whereby any foreign particles can readily be removed; and all ,elanger of merring'or ruining the plate en- "enable/the mold to be more easily-handled than heretofore, and greater efiicienoy and I olespeteh secured in operetion,

The above and other ob eet's enilietlvane0 qes of my invention willeppeer feoi'nthe following oleseription. tekenin connection with the accompenyin'g drawings; and be :DPECISGIYV defined 1n the eppendecl claims. I wish to have it understood, however, that fifications in the :details ofiny invention that I may fi'mi it avisehlelto adopt; pro-'- IVlClGd oifcourse that suchflmodifications fell avithin the sco; e and spiritof my invention sthe claims specify thesamei,

3: On said drawings: Flggrel we, plan showing a plaster imprewionqor-pettern 1 0f the roof of a human mouthffor which a;

o-pletezis desired; this tt r 'n o'tlellfor the molctiiaskjF g; y t-wmol' fla usedlin the practice Of my invention Fig Specification of Letters P's tent.

tirely obviated; unol it further object is tothe disclosure herein sets forth but one em- ,hodlment or my inventive idea;- and that ,jthsirnn sin rns PATENT osnion,

nrennn'rus'ron MAKING PLATES roe nmmiomn rE'E'rH;

in u receiving flask for the operation. of casting; Fig. 7 is an elevation of the moldcontaining flask illustrating the entrance to the mold cavity; 'and Fig. 8 is a similar view of the flask seen from the opposite nd.

parts onall the views.

In the manufacture of mouth plates it Patented Nov. 28; 1916.

Application fileci January 6, 1916. Serial No. 7D,61 4.- I

3 is a, sectional view showing such a mold The some numbers indicate the same I has previously been the custom to begin 1 with an exact pattern, generally of plaster, having a specially formed surface eorre-. spending to the interior of an individual mouth for which. a plate'is to he produced. Such a pattern is shown at 1 in Fig. 1. If the plate is to fit the roof of the mouth, the surface-2 of the pattern 1 will he shaped by putting a. muss'of soft plaster on an implement- 3,:1nil forcing the mass against the 1 root of the mouth to receive a true imprint thereof. The plaster is then removed, set up and a reproduction of the surfacefl is mucle'hy covering the pattern 1 with pies tenor the like and thereby forming the r'n'oclel. 1; Figs-2, 8, i and. 5;; which goes "85 into the imold flask. The surfece 2'? of this modell will' correspondexectly to the surface, 2, only it will be convex "where the first surfuce was concave and vice verse. after the model is separated. from the pat tern; its surface 2' is given a coating, as of wax 4. Themodel with its Wax coating is then embedded in aplestic mold of any suitable composition :Which isfpscked into suitable flask or casing, an aperture leedingjtq the wax of -course being present to enable the Wax to'he remove-lei. When the mold has set it .isheeted,- so that the wax nieltsend can be poured out.

y In conse ,,.quence amold-cavity is-left in the plastic ,..0f Sl10ll description as to form a,'plete of the. necessery thickness and contour wheii F-zzholtenmeterielis poured into it.- i y V -iiisprooesshes a. number of drawbacks; fokiief arnongjwhich is the impossibility of mekjingfsurethat the" mold is perfectbefore tiliging' in the usual way, The .molcllot relieved of any extraneous substances that may be inside of it. Therefore the wax, especially if not entirely pure. will frequently leave dirt in the mold-cavity; and in such a case'the plate will be a very poor one. In fact, plates made by this method are nearly always marked or rough. and as many as ten per cent. will be so defective as to be totally useless. Further likelihood of injury to the plates is also encountered after the casting is finished and the plate taken out. This stage requires that the mold. which has now become hard. be broken up till the plate is" freed from the plaster. and damage to the plate when the plaster is being shattered, can easily take place. Further, such a mold can be used but once.

In my invention I avoid the disadvantages above mentioned by using a mold-containing flask 5, comprising a pan-shaped section 6 with rim 7, a ring-shaped section 8, and a third section 9; so arranged that the flask can not.only be taken apart to allow the mold-cavity to be examined and wipedout,

if need be, but also manipulated and moved about, when closed up, by the operator; and opened when the plate is finished and ready to be extracted, without any risk whatever. With this flask a. mold can he used Several times.

v The section 8 has the same'contour as the rim 7,.and has fingers or projections 10. to receive the rim and enable the rim and the section 8 to be fitted. edge to edge, together; and the section 9 has similar projections to engage the section 8. Further, the rim 7 and the section 8 will have recesses 11, which register. when the flask is made up, to make a relatively large aperture, leading to the mold-cavity, as clearly seen in Fig. 7. Of

course suitable recesses may be provided to receive the projections 10. I

I use the flask, for. example, by taking the section 9 as the bottom and placing thereon the section 8, andthen filling'with plastic substance, such as plaster, as shown in Fig. 2. The model 1' with wax coating 4 on its special surface 2, is then placed -on the topof the plaster, preparatory to covering'it entirely. The. model may be laid so that the surface 2 and wax coating 4 may be up or down, as the'result in either case will be-the same. Then the pan-shaped section 6 is filled with plaster, and placed on over the model-1, the rim 7 fitting upon the section 8, and being centered by the projections 10. In order to allow, of the flask being opened and the mold divided after the plaster has hardened, I give the top of the plaster inclosed by the rmg-shaped'section 8 adjacent the upper edge of the section, a. coating of shellac or soap or other 6 to be separat;d from the plaster in the section 8 after the mold has set. Fig. 3 shows the pen-shaped section about to close over the pattern and embed the same in the mold completely.

When the flask is closed the sections will fit tightly together as indicated in Fig. 4; the

fingers or projections 10 retaining the ec tions in true relative positions. Enough of the plaster will be removed from the aperture furnished by the recesses 11 to expose the edge of the wax, and when the plastic has set, the flask with the mold therein can be heated enough to melt the wax and the latter caused to pour out through-the hole in question; whereby the mold-cavity will be created. j

My method of producin mouth plates has nowreached the stage w on the flask canv be opened in order to inspect the mold-cavity; and the pan-shaped section 6 is separated from'the sections 8 and 9 which remain together. The'pla-ster in the Section 6 separates easily from the rest of the plaster because of the shellac, and both the top and bottom of the mold-cavity can be carefully' looked over and any dirt or other foreign matter in this cavity can be easily gotten rid of. The flask is now closed by a ain pressing the sections together, and the mo ten material can now be poured into the mold- 'cavity through the large aperture leading to the same. Fig. 5 indicates the manner in which the .mold can be opened for the above purpose.

The wax may be removed'from the investment material in the sections 6 and 8 in anyway that will thoroughly clean the mold.

In order toefl'ect the casting, the flask 5 is supported with the aperture leading to the.

mold-cavity on top and this aperture will re.-.

ceive enough molten material, such as aluminum, fill the mold-ca-vity. Before pouring the. aluminum into the aperture the flask 5 is-placed into a larger. flask 18, which loosely and snugly receives it, asshown in Fig. 6; and compressed air or some other pressure agent will be employed to force the molten aluminum into the mold-cavity before it solidifies. As shown in Fig. 6, the flask 13 is open at both ends, the upper end being enlarged, and is in effect. approximately funnel-shaped; 'so that the flask 5, which tapers from top to bottom, can rest in contact with the inside of the flask 13, snugly fitting the same and secured in proper position thereby. The large end of the fled: 13 will receive a cover provided with suit able packing, to make it tight, and through this cover leads a conduit b which the pressure agent is supplied. e air impel; the

- suflicient tightness by reason of the fingers molten aluminum down into the cavity, and inasmuch as'the mold is more, or less porous any air which passes to the inside of the flask 5 can escape therefrom between the sections and through theexit openings 14 in the section 6 and section 9. If desired, registering recesses may be provided in the "rim 7 and section 8 in order to'increase the number of exit openings, as shown in Fig, 8. After the aluminum fills the mold-cavity the closed flask 5 is removed from the flask 13 and. taken apart, and the casting is finished.

It is understood of course that the come pressed air issuing from the flask 5 will es? cape through the bottom of the fiaskx13; as this flask rests upon a perforated support.

The flask 5 will of course be of such size that it will fit the flask 13 with the fiat outer faces of the sections 6 and 9 close to the inner surfaces of the flat sides of the outer flask. I make the sections of the flask 5 so that they will'hold together with '10; but additional means to produce this eifect may be employed if needed. If desired, suitable means may also be employed to prevent too much compressed air from passing between the flat facesor; the flask 5 and'the flask 13; so as to make sure that the molten material may be properly forced into the mold cavity. 3 I

By means of my invention a mold is very easily handled,- and can be put into the flask 13 and taken out with practically no.

effort whatever. Furthermore, the plastic mold does not haveto be broken up by force after the casting operation is'finished; and, owing to the accessibility of the mold-v cavity, the possibility of dirttherein spoiling the casting is entirely eliminated. Acctual experiments have demonstrated t jat not more than two per cent. of castings ma e by my process and apparatus are defective under any circumstances and if the-operator is ordinarily careful the spoiling of a plate will be a very rare occurrence. Furthermore by locating the exit openings at various. oints with respect to the mold cavity, t e compressed air tends to tribute the molten material more evenly in the mold-cavity, and this fact likewise helps to'increase the value and practical merit of my invention by insuring a high. grade output. Afterthefirst plate is finished the mold (ante used over to make a number of additional plates, and 1's notby .any means limited to a single plate like molds made by the old method, which require tobe broken and thus destroyed before the plate can be taken out. Of course the flask 5 can also he used by taking the section 6 first to receive the pattern 1, and then placing the sections 8 and 9 on top of it. When the sedtion 6 is filled and the pattern in posistood.

tion, the section is added and filled'till the placing the; section 9 on thesection 8 as a lid or cover. This way is often a good deal easier and morepractical;

My invention enables me to castplates of aluminum, gold or other metal for either pattern is covered, and the flask closedby the roof of (the mouth or the lower jaw;

and either a forced blast, such as a medium under pressure, or' a suction blast can be utilized to impel the molten material into the mold cavity. Other methods of forcing the molten material into the mold cavity 4 may of course be resorted to.

The flask 5 may; also be carriedin teen-- trifugal machine, and centrifugal force instead of a pressure agentiutilized to make sure of filling the mold-cavity Any suitable plastic. composi employed in the mold, as will be under- Having described my invention, what I believe to be new and desire to secure and protect-by Letters Patent of the United States is: 1. The combination with a flask having a tion may be relatively-large end and a relatively small end, and being provided with a pair of opposite parallel sides and'a pair of oppositeconverging sides, of a tapering flask likewise provided with a large i-nd and, a' small end, and having parallel outer faces received between the parallel sides of thefirst-named flask, said tapering flask com prising separable sections inclosing a mold ,cavitywhose periphery lies substantially ,in the plane of the meeting edges of adjacent sections, said tapering flask being-enshaped section similar in outline to the rim,

and a third section, said sections havingprojections and recesses to enable them to be fitted together, sothat the ringshaped section will coincidewith the rim, and the third section with the ring-shaped section,

the rim and the ring-shaped section having registering recessesforming an aperture in the flask to admit molten material to the mold-cavity, said aperture extending across substantially the width of the mold-cavity, the rim-and the ring-shaped section having other registering recesses forming exit openings, the bottom of the pan-shaped section and the third section also being provided with exit openings, said openings I being located at various points with respectto the m01d-cavity, whel eby a pressure of two subscribing Witnesses, this 15th day agent may be applied through thelapertxilge of December, 1915. to force the molten material into t 1e mo e cavity, and be subsequently enabled to LALE SPIJNKLE' 5 escape from the flask. Witnesses:

In testimony whereof, I have signed my ROBERT Fm'n x, name to this specification, in the presence \VM. F. NICKEL. 

